The Hamiltonian \(H_{\textrm {\tiny YM}}\)  of the gauge theory associated
to any foliation of the surface \(\Sigma \)  is given in terms of
the quadratic Casimir operator \(C_2\) 
by [1]}, [2]}
\(H_{\textrm {\tiny YM}}=\frac{e^2}{2}\, L\, C_2+e^2\,L\,\upsilon _2 \ ,\) 
